The use of a cruciform anterior spinal hyperextension orthosis is well known and widely accepted in the treatment of certain specific abnormalities of the spine. A cruciform orthosis, which has gained a wide degree of acceptance, is disclosed in U.S. Pat. No. 4,173,973 entitled, "Hyperextension Back Brace" issued Nov. 13, 1979 to David J. Hendricks. The patent was reissued as RE 31,564 on Apr. 24, 1984. A commercial embodiment of the cruciform orthosis, which is taught in the patent, is shown in a catalog sheet entitled, "The CASH Orthosis" published by Ralph Storrs, Inc. of 197 South West Avenue, Kankakee, Ill. The catalog sheet has a copyright date of 1985.
The known cruciform orthosis applies a force to the anterior of a patient's body and a balanced force to the posterior of the body and thus the spine. The force on the patient's anterior is generally applied by two pads. One pad is positioned in the patient's pubic area and the other is positioned on the sternum. The forces from the two pads on the patient's anterior are balanced by a back strap which is in engagement generally with the lumbar area of the posterior to apply a constant force to the spine. Some patients suffer some discomfort when they wear the known cruciform orthosis because the sternal pad rests on the sternum where there is very little muscle and fat to dissipate the load from the sternal pad.
The use of pectoral pads in a back brace is well known and accepted in the art. A Bigg back brace with pectoral pads is taught at page 183 of the Orthopaedic Appliances Atlas, Volume 1 published by J.W. Edwards of Ann Arbor, Mich., 1952. The Bigg back brace has two pectoral pads supported by an upright which is located on the posterior of the patient. The pectoral pads are supported by bars which curve around opposite sides of the patient's body, thus giving rise to "cowhorns" as an identification of the arrangement. The "cowhorns" arrangement is heavy and is uncomfortable for the patient.
In view of the undesirability of the "cowhorn" arrangement, a prior art T-support 3, such as that shown in FIG. 8, has been used in the prior art cruciform orthosis instead of a single sternal pad. T-support 3 has an upright 5 which is adapted to be connected to an upper vertical arm of the Hendricks cruciform orthosis in substitution for the movable arm part of the Hendricks device. A cross memmber 7 is pivotally connected to upright 5 by hinge 9. A conventional pectoral pad 11 is fixed on each of the opposite ends of crossmember 7 of the T-support. Though the use of the two pectoral pads provides a greater degree of comfort over a single sternal pad, the pectoral pads do not accommodate themselves to movement of the patient relative to the subject orthosis.